We have only seen a handful over the years.

The registers would originally have been closer to black - exposure to the sun in Sharm el-Sheikh probably helped fade them a bit to the current chocolate!

Seems to be the norm for them, the above example is similarly faded. There were a few problems with UV stability of various paints in this period for Heuer; some of the blues are prone to turn violet in the Cal 15 Monacos and Carreras that arrived just after we first saw these Autavias appearing.